[Toxicological Evaluation of Intravenous Formulation of Rifapentine.]

Rifapentine belongs to the most potent antituberculosis drugs. Nevertheless, there are some limitations for its clinical use because of the low aqueous solubility and side effects. A technological approach to development of rifapentine intravenous formulation based on human serum albumin was described earlier and its efficacy against experimental tuberculosis was estimated. Toxicological evaluation of that water-compatible form of rifapentine revealed its low acute toxicity (LD₅₀ 340 mg/kg). Chronic toxicity tests of both the oral substance and the injectable formulation of rifapentine demonstrated similar adverse effects. However, in contrast to the conventional oral formulations, the intravenous formulation of rifapentine had no gastrointestinal toxic effects or cardiotoxicity, thus suggesting its usefulness for clinical application.